The split-screen device codenamed as the Sony S2 tablet is going to be an AT&T exclusive in the United States. AT&T just confirmed that it will offer the S2 through its 4G HSPA+ network later this year, though it did not include a price or release date – though Sony previously said it would release the S2 sometime during Fall 2011.

You may recall the S2 as the Kyocera-Echo-like tablet that has two 5.5-inch screens paired in a clamshell format. When unfolded, the S2 screens can be used in conjunction to display one screen or split apart for multitasking and gaming. The device will feature a customized version of Android Honeycomb and additional entertainment options from Sony media and PlayStation gaming services.

AT&T Xperia Play

Today’s announcement follows yesterday’s revelation that AT&T would also begin selling the Android 2.3-powered Sony Ericsson Xperia Play. Verizon was first to offer the device, but AT&T will soon sell a “Stealth Blue” color version of the phone capable of using its HSPA+ network. The phone will have a 1 GHz Qualcomm processor, 4-inch screen, and most of the highs-and-lows cited in our Verizon Xperia Play review. However, there will be one difference: AT&T’s version of the Play has elements of the Timescape user interface while Verizon runs stock Android 2.3.

AT&T has ramped up its Android efforts this year, so its no surprise that the company is introducing both a network-tied tablet and a new phone. Some may scoff at the S2 – truth be told, I’m not very excited about it either – but the Xperia Play is a respectable phone for a niche market. We can only hope the price will be as respectable once the release date is confirmed.